Nowadays numerous types of beds for hospital stays are known in which sections of the bed surface are adjustable at the upper and lower parts of the back, at the thighs and at the legs, in order to allow the elevation of the backrest or of the leg rest with an electric or manual system.
Such beds are essential for patients with reduced motor capacity; however, very often the forward inclination of the backrest, in order to facilitate the sitting positioning of the patient, causes the patient to slip toward the footboard of the bed. Nowadays this is seen as an important problem to be solved for the health of the patient, who must be continuously repositioned in order to reduce compression in the chest region and of the pelvis, in order to facilitate respiration and improve postural comfort.
In an attempt to solve this problem, solutions have been devised with a backrest that can be moved by roto-translation: while the rotation results in the lifting of the backrest, simultaneously the translation results in its retraction, toward the headboard of the bed, so as to compensate the thrust of the patient toward the footboard.
However, to date this solution has not been found to be sufficient to solve the problem, because the patient seated on the bed is still subject over time to sliding toward the footboard, and the need is therefore felt to identify an improvement.